--%>
Assignment Help - homework help

Problem on work of compression

A diesel engine operates devoid of a spark plug by using the high-temperature gas produced throughout the compression stage to ignite the fuel. During a typical compression, pure air that is originally at 21 °C and 0.95 bar is reversibly and adiabatically compressed to 1/20 of its original(actual) volume by the piston, as shown in the figure below.

a) If air is assumed to obey the ideal gas equation of state, find out the pressure and temperature in the cylinder at the end of the compression. The constant-pressure heat capacity of air varies with temperature and is given by

Cp/R = 3.3 + 6x10-4

b) What is the work of compression in J/mol of air?

c) Is the ideal gas law a good approximation in this case? Why?

2455_ideal gas law.jpg

   Related Questions in Mechanical Engineering

  • Q : Safety in Product design specification

    Safety: The specifications should state the possible abuse and misuse the product might be subjected to. Warning labels and instructions on safe operation of the product should be given. The designer can be held accountable for any accidents that migh

    		•
  • Q : Hard links Explain the term hard links?

    Explain the term hard links?

    		•
  • Q : Carburetion A carburetor's primary

    A carburetor's primary function is to mix proper proportions is?

    		•
  • Q : Problem on work of compression A diesel

    A diesel engine operates devoid of a spark plug by using the high-temperature gas produced throughout the compression stage to ignite the fuel. During a typical compression, pure air that is originally at 21 °C and 0.95 bar is reversibly and adiabatically compress

    		•
  • Q : Undamped single degree of freedom (a)

    (a) The response for an undamped single degree of freedom system under free vibration is given as where ωn is the natural frequency and A and B are unknown that can be determined from the initial conditions. The response 

    		•
  • Q : Problem on degree of freedom Draw a

    Draw a frequency-response curves for a damped single degree of freedom system subjected to a harmonic excitation under three different damping ratios. System has a natural frequency of ωn as the forcing frequency of the excitation is ω. Describe

    		•
  • Q : Size and weight in Product design

    Size and weight: If the product is particularly small the cost may be increased if more precise manufacturing methods are demanded. Weight restriction will as well influence materials to be utilized: this in turn will influence the manufacturing proce

    		•
  • Q : Problem on damping coefficient Vertical

    Vertical suspension system of a car can be modeled as single degree of the freedom system. Consider that the car with mass m consists of four shock absorbers with equal stiffness and damping of k and c, corresspondingly: (a) Due to

    		•
  • Q : Problem on Ideal gas process A) Air at

    A) Air at 4MPa and 3000C enters a will insulated turbine operating at steady state with negligible velocity. The air expands to an exit pressure of 100KPa. The exit velocity and temperature are 90 m/s and 1000C respectively. The diameter of the e

    		•
  • Q : Fly ball governor in the hydrualic

    How the fly ball governor is used along with the hydraulic control?

    		•